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Furnace and AC

Good day, I’m a newbie trying to get a handle on some burning questions that I have.

I just bought my second home in May knowing the furnace and A/C need to be replaced. Both are working but are looking a little rough, but I have time to ask the appropriate questions. The home is 2300 Sqft 2 story with a basement. I live in Niagara and the winters are rough at points. Currently installed is a 100, 000 BTU Mid Eff and a 2.5 TON A/C.

I’ve had numerous quotes all are about the same. I’m looking for high efficiency natural gas of 92% AFUE or better, preferably better. For the A/C I’m looking for something 14 Seer or better.

My issue is only one of the dealers actually checked my duct work to see what size it was, and the same guy calculated the heat loss for my home which he said would be around 45,000 BTU due to windows etc. I found him to be the most professional.

I had multiple quotes from CARRIER they all said 60 000 BTU and 2.5 Ton A/C. Why is it both TRANE and BRYANT are saying 80 000 BTU? All are the dual ECM’s. Why is BRYANT saying go with a 3 TON? What is the general census on 60 v/s 80 000 BTU given my house size?

One of the dealers said the 3 Ton A/C would be too much for my house and would cause the motor/ compressor to keep kicking off and on and the bottom floor would be cool while the top floor wouldn’t.

The explanation I got for the 60 v/s 80 000 BTU is that 80 would be overkill for the size of the house. If I stayed with 60 000 the furnace would be running at about 46 000 BTU for the majority and 60 000 when it needs that extra kick.

Another dealers explained that because it’s a 2 stage its better to go with 80 because it would be running at 56, 000 most of the time and 80 000 BTU for those really cold winter days.

Ask neighbors for references. Then go with the contractor that you feel most comfortable with. Make sure they do load calcs. The ones going with the 80K are probably using "rules of thumb" Guesstimating and while the units will work they won't be the most comfortable and efficient.

I’ve spoken to neighbours, none have done the upgrades yet, a couple are waiting for me to do all of the leg work. I just want to know what the science is.

1. What are the reasons for going to 80 000 as opposed to 60 what are the pros and cons, the same with the A/C with the 2.5 Ton V/S the 3 Ton in terms of my given 2300Sqft and a tight home?

2. What is the better units in the experts opinions Carrier V/S Trane V/S Bryant.

My dad just did his system he has a 90 year old home, mines only 20. Both are the same Sqft. Mine is well insulated throughout and tight (I did an energy audit). He got the 80 and a 3 ton 15 Seer he has no complainants. I think the 60 and the 2.5 Ton will work but will it be enough for the crazy times in the winter. My current set up with the 100 000 BTU Mid efficiency I feel the cold in the house.

I was most happy with the dealer that gave me most of the info and actually explained things rather then do the old “ya this should work” out of 7 dealers of various companies only one did the calculations and explained it to me. It’s fine for a dealer to tell me I need an 80 because they’re going to charge me more for it, but do I need that? Same with the A/C. I just want to know what the “NEUTRAL EXPERTS” have to say about the equipment differences. And whose got the best product.

Carrier and Bryant are 1 in the same. FYI. You take the Bryant tag off and it is a Carrier. Take the Carrier tag off and it is a Bryant. The only different is the Blue Carrier plastic tag and Red Bryant plastic tag.

Carrier and Bryant are 1 in the same. FYI. You take the Bryant tag off and it is a Carrier. Take the Carrier tag off and it is a Bryant. The only different is the Blue Carrier plastic tag and Red Bryant plastic tag.

...My dad just did his system he has a 90 year old home, mines only 20. Both are the same Sqft. Mine is well insulated throughout and tight (I did an energy audit). He got the 80 and a 3 ton 15 Seer he has no complainants. I think the 60 and the 2.5 Ton will work but will it be enough for the crazy times in the winter. My current set up with the 100 000 BTU Mid efficiency I feel the cold in the house.

Did you SEE a copy of the heat calc? Seems to me that your heat loss of 45000 might be on the low side. I live in the Philadelphia area in a 2500 sf 2 story with great windows, very good insulation, etc. My winter design temperature is 14*; your's is 7*. Heat loss (mine) is just under 60,000.

Is your current furnace a single stage unit? If you're experiencing temperature swings, this will not be comfortable. My house is also (in 3 months) 20 years old and I am looking into replacing my system. Based upon what I've read here and elsewhere, if your furnace is single stage w/standing pilot, it is about 60 - 65% efficient. This translates to 60,000 - 65,000 BTUs being 'delivered'.

Go with the guy that was the most professional and did the load calcs. It is on him if it is undersized/oversized. The equipment doesn't matter as long as it is installed properly, both Carrier and Trane are good units.

I’ve done the load calc myself, what I got for results were 65, 361 BTUH Heat Loss and 25, 985 BTUH Heat Gain. So if my calcs are done correctly I should be using an 80,000 BTU furnace and a 2.5 Ton.

My current 100,000 BTU furnace is a single stage Mid with a standard pilot and from what I know it is about 60-65% efficient. The guy that did the calcs has been in the industry for at least 25yrs, so maybe I’ve done something wrong. One thing one of the dealers told me was something about having to make the ducts bigger for an 80 to work. My main run plenium is 8 x 18 inches and the two min trees to the house are 8 x 14 inches. The dealer said even with the 60,000 BTU I’d have to get a bigger plenium 12 x 16, to move the air, but the main tree was ok.